This is the description of the JavaScript API bindings for the One Wire Bricklet. General information and technical specifications for the One Wire Bricklet are summarized in its hardware description.
An installation guide for the JavaScript API bindings is part of their general description.
The example code below is Public Domain (CC0 1.0).
Download (ExampleReadDS18B20Temperature.js)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 | var Tinkerforge = require('tinkerforge');
var HOST = 'localhost';
var PORT = 4223;
var UID = 'XYZ'; // Change XYZ to the UID of your One Wire Bricklet
var ipcon = new Tinkerforge.IPConnection(); // Create IP connection
var ow = new Tinkerforge.BrickletOneWire(UID, ipcon); // Create device object
var writeCommandPromise = function(ow, identifier, command) {
var promise = new Promise(function(resolve, reject) {
ow.writeCommand(identifier, command, function(status) {
resolve(status);
});
});
return promise;
}
var writePromise = function(ow, data) {
var promise = new Promise(function(resolve, reject) {
ow.write(data, function(status) {
resolve(status);
});
});
return promise;
}
var readPromise = function(ow) {
var promise = new Promise(function(resolve, reject) {
ow.read(function(data, status) {
resolve(data, status);
});
});
return promise;
}
var timeoutPromise = function(millis) {
var promise = new Promise(function(resolve, reject) {
setTimeout(function () {
resolve();
}, millis);
});
return promise;
}
ipcon.connect(HOST, PORT,
function (error) {
console.log('Error: ' + error);
}
); // Connect to brickd
// Don't use device before ipcon is connected
ipcon.on(Tinkerforge.IPConnection.CALLBACK_CONNECTED,
async function (connectReason) {
await writeCommandPromise(ow, 0, 78); // WRITE SCRATCHPAD
await writePromise(ow, 0); // ALARM H (unused)
await writePromise(ow, 0); // ALARM L (unused)
await writePromise(ow, 127); // CONFIGURATION: 12-bit mode
// Read temperature 10 times
for(var i = 0; i < 10; ++i) {
await writeCommandPromise(ow, 0, 68); // CONVERT T (start temperature conversion)
await timeoutPromise(1000);
await writeCommandPromise(ow, 0, 190); // READ SCRATCHPAD
var t_low = await readPromise(ow);
var t_high = await readPromise(ow);
var temperature = t_low | (t_high << 8);
// Negative 12-bit values are sign-extended to 16-bit two's complement
if (temperature > (1 << 12)) {
temperature -= 1 << 16;
}
// 12 bit-mode measures in units of 1/16°C
console.log('Temperature: ' + temperature/16.0 + ' °C');
}
}
);
console.log('Press key to exit');
process.stdin.on('data',
function (data) {
ipcon.disconnect();
process.exit(0);
}
);
|
Download (ExampleReadDS18B20Temperature.html), Test (ExampleReadDS18B20Temperature.html)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 | <!DOCTYPE html>
<html>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<head>
<title>Tinkerforge | JavaScript Example</title>
</head>
<body>
<div style="text-align:center;">
<h1>One Wire Bricklet Read DS18B20 Temperature Example</h1>
<p>
<input value="localhost" id="host" type="text" size="20">:
<input value="4280" id="port" type="text" size="5">,
<input value="uid" id="uid" type="text" size="5">
<input value="Start Example" id="start" type="button" onclick="startExample();">
</p>
<p>
<textarea readonly id="text" cols="80" rows="24" style="resize:none;"
>Press "Start Example" to begin ...</textarea>
</p>
</div>
<script src="./Tinkerforge.js" type='text/javascript'></script>
<script type='text/javascript'>
var ipcon;
var textArea = document.getElementById("text");
function startExample() {
textArea.value = "";
var HOST = document.getElementById("host").value;
var PORT = parseInt(document.getElementById("port").value);
var UID = document.getElementById("uid").value;
if(ipcon !== undefined) {
ipcon.disconnect();
}
ipcon = new Tinkerforge.IPConnection(); // Create IP connection
var ow = new Tinkerforge.BrickletOneWire(UID, ipcon); // Create device object
var writeCommandPromise = function(ow, identifier, command) {
var promise = new Promise(function(resolve, reject) {
ow.writeCommand(identifier, command, function(status) {
resolve(status);
});
});
return promise;
}
var writePromise = function(ow, data) {
var promise = new Promise(function(resolve, reject) {
ow.write(data, function(status) {
resolve(status);
});
});
return promise;
}
var readPromise = function(ow) {
var promise = new Promise(function(resolve, reject) {
ow.read(function(data, status) {
resolve(data, status);
});
});
return promise;
}
var timeoutPromise = function(millis) {
var promise = new Promise(function(resolve, reject) {
setTimeout(function () {
resolve();
}, millis);
});
return promise;
}
ipcon.connect(HOST, PORT,
function(error) {
textArea.value += 'Error: ' + error + '\n';
}
); // Connect to brickd
// Don't use device before ipcon is connected
ipcon.on(Tinkerforge.IPConnection.CALLBACK_CONNECTED,
async function (connectReason) {
await writeCommandPromise(ow, 0, 78); // WRITE SCRATCHPAD
await writePromise(ow, 0); // ALARM H (unused)
await writePromise(ow, 0); // ALARM L (unused)
await writePromise(ow, 127); // CONFIGURATION: 12-bit mode
// Read temperature 10 times
for(var i = 0; i < 10; ++i) {
await writeCommandPromise(ow, 0, 68); // CONVERT T (start temperature conversion)
await timeoutPromise(1000);
await writeCommandPromise(ow, 0, 190); // READ SCRATCHPAD
var t_low = await readPromise(ow);
var t_high = await readPromise(ow);
var temperature = t_low | (t_high << 8);
// Negative 12-bit values are sign-extended to 16-bit two's complement
if (temperature > (1 << 12)) {
temperature -= 1 << 16;
}
// 12-bit mode measures in units of 1/16°C
textArea.value += 'Temperature: ' + temperature/16.0 + ' °C';
}
}
);
}
</script>
</body>
</html>
|
Generally, every function of the JavaScript bindings can take two optional
parameters, returnCallback
and errorCallback
. These are two user
defined callback functions. The returnCallback
function is called with the
results as arguments, if the function returns its results asynchronously. The
errorCallback
is called with an error code in case of an error. The error
code can be one of the following values:
The namespace for the JavaScript bindings is Tinkerforge.*
.
BrickletOneWire
(uid, ipcon)¶Parameters: |
|
---|---|
Returns: |
|
Creates an object with the unique device ID uid
:
var oneWire = new BrickletOneWire("YOUR_DEVICE_UID", ipcon);
This object can then be used after the IP Connection is connected.
BrickletOneWire.
searchBus
([returnCallback][, errorCallback])¶Callback Parameters: |
|
---|---|
Returns: |
|
Returns a list of up to 64 identifiers of the connected 1-Wire devices. Each identifier is 64-bit and consists of 8-bit family code, 48-bit ID and 8-bit CRC.
To get these identifiers the Bricklet runs the SEARCH ROM algorithm, as defined by Maxim.
The following constants are available for this function:
For status:
BrickletOneWire.
resetBus
([returnCallback][, errorCallback])¶Callback Parameters: |
|
---|---|
Returns: |
|
Resets the bus with the 1-Wire reset operation.
The following constants are available for this function:
For status:
BrickletOneWire.
write
(data[, returnCallback][, errorCallback])¶Parameters: |
|
---|---|
Callback Parameters: |
|
Returns: |
|
Writes a byte of data to the 1-Wire bus.
The following constants are available for this function:
For status:
BrickletOneWire.
read
([returnCallback][, errorCallback])¶Callback Parameters: |
|
---|---|
Returns: |
|
Reads a byte of data from the 1-Wire bus.
The following constants are available for this function:
For status:
BrickletOneWire.
writeCommand
(identifier, command[, returnCallback][, errorCallback])¶Parameters: |
|
---|---|
Callback Parameters: |
|
Returns: |
|
Writes a command to the 1-Wire device with the given identifier. You can obtain
the identifier by calling searchBus()
. The MATCH ROM operation is used to
write the command.
If you only have one device connected or want to broadcast to all devices you can set the identifier to 0. In this case the SKIP ROM operation is used to write the command.
The following constants are available for this function:
For status:
BrickletOneWire.
setCommunicationLEDConfig
(config[, returnCallback][, errorCallback])¶Parameters: |
|
---|---|
Callback Parameters: |
|
Returns: |
|
Sets the communication LED configuration. By default the LED shows 1-wire communication traffic by flickering.
You can also turn the LED permanently on/off or show a heartbeat.
If the Bricklet is in bootloader mode, the LED is off.
The following constants are available for this function:
For config:
BrickletOneWire.
getCommunicationLEDConfig
([returnCallback][, errorCallback])¶Callback Parameters: |
|
---|---|
Returns: |
|
Returns the configuration as set by setCommunicationLEDConfig()
The following constants are available for this function:
For config:
BrickletOneWire.
getSPITFPErrorCount
([returnCallback][, errorCallback])¶Callback Parameters: |
|
---|---|
Returns: |
|
Returns the error count for the communication between Brick and Bricklet.
The errors are divided into
The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.
BrickletOneWire.
setStatusLEDConfig
(config[, returnCallback][, errorCallback])¶Parameters: |
|
---|---|
Callback Parameters: |
|
Returns: |
|
Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.
You can also turn the LED permanently on/off or show a heartbeat.
If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.
The following constants are available for this function:
For config:
BrickletOneWire.
getStatusLEDConfig
([returnCallback][, errorCallback])¶Callback Parameters: |
|
---|---|
Returns: |
|
Returns the configuration as set by setStatusLEDConfig()
The following constants are available for this function:
For config:
BrickletOneWire.
getChipTemperature
([returnCallback][, errorCallback])¶Callback Parameters: |
|
---|---|
Returns: |
|
Returns the temperature as measured inside the microcontroller. The value returned is not the ambient temperature!
The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.
BrickletOneWire.
reset
([returnCallback][, errorCallback])¶Callback Parameters: |
|
---|---|
Returns: |
|
Calling this function will reset the Bricklet. All configurations will be lost.
After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!
BrickletOneWire.
getIdentity
([returnCallback][, errorCallback])¶Callback Parameters: |
|
---|---|
Returns: |
|
Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.
The position can be 'a', 'b', 'c', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). A Bricklet connected to an Isolator Bricklet is always at position 'z'.
The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.
Virtual functions don't communicate with the device itself, but operate only on the API bindings device object. They can be called without the corresponding IP Connection object being connected.
BrickletOneWire.
getAPIVersion
()¶Returns: |
|
---|
Returns the version of the API definition implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.
BrickletOneWire.
getResponseExpected
(functionId[, errorCallback])¶Parameters: |
|
---|---|
Returns: |
|
Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.
For getter functions this is enabled by default and cannot be disabled,
because those functions will always send a response. For callback configuration
functions it is enabled by default too, but can be disabled by
setResponseExpected()
. For setter functions it is disabled by default
and can be enabled.
Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.
The following constants are available for this function:
For function_id:
BrickletOneWire.
setResponseExpected
(functionId, responseExpected[, errorCallback])¶Parameters: |
|
---|---|
Returns: |
|
Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled.
Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.
The following constants are available for this function:
For function_id:
BrickletOneWire.
setResponseExpectedAll
(responseExpected)¶Parameters: |
|
---|---|
Returns: |
|
Changes the response expected flag for all setter and callback configuration functions of this device at once.
Internal functions are used for maintenance tasks such as flashing a new firmware of changing the UID of a Bricklet. These task should be performed using Brick Viewer instead of using the internal functions directly.
BrickletOneWire.
setBootloaderMode
(mode[, returnCallback][, errorCallback])¶Parameters: |
|
---|---|
Callback Parameters: |
|
Returns: |
|
Sets the bootloader mode and returns the status after the requested mode change was instigated.
You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.
This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.
The following constants are available for this function:
For mode:
For status:
BrickletOneWire.
getBootloaderMode
([returnCallback][, errorCallback])¶Callback Parameters: |
|
---|---|
Returns: |
|
Returns the current bootloader mode, see setBootloaderMode()
.
The following constants are available for this function:
For mode:
BrickletOneWire.
setWriteFirmwarePointer
(pointer[, returnCallback][, errorCallback])¶Parameters: |
|
---|---|
Callback Parameters: |
|
Returns: |
|
Sets the firmware pointer for writeFirmware()
. The pointer has
to be increased by chunks of size 64. The data is written to flash
every 4 chunks (which equals to one page of size 256).
This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.
BrickletOneWire.
writeFirmware
(data[, returnCallback][, errorCallback])¶Parameters: |
|
---|---|
Callback Parameters: |
|
Returns: |
|
Writes 64 Bytes of firmware at the position as written by
setWriteFirmwarePointer()
before. The firmware is written
to flash every 4 chunks.
You can only write firmware in bootloader mode.
This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.
BrickletOneWire.
writeUID
(uid[, returnCallback][, errorCallback])¶Parameters: |
|
---|---|
Callback Parameters: |
|
Returns: |
|
Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.
We recommend that you use Brick Viewer to change the UID.
BrickletOneWire.
readUID
([returnCallback][, errorCallback])¶Callback Parameters: |
|
---|---|
Returns: |
|
Returns the current UID as an integer. Encode as Base58 to get the usual string version.
BrickletOneWire.
DEVICE_IDENTIFIER
¶This constant is used to identify a One Wire Bricklet.
The getIdentity()
function and the
IPConnection.CALLBACK_ENUMERATE
callback of the IP Connection have a device_identifier
parameter to specify
the Brick's or Bricklet's type.
BrickletOneWire.
DEVICE_DISPLAY_NAME
¶This constant represents the human readable name of a One Wire Bricklet.